The official Japanese Pokemon Twitter has revealed Slowking from Rage of the Broken Sky. Thanks goes to Jake C. for the translation!
Ability: King’s Inspiration
Once during your turn (before your attack), you may flip a coin. If heads, choose an Energy attached to your opponent’s Active Pokemon and move it to 1 of his or her Benched Pokemon.
[W][C] Psych Up: 40 damage. During your next turn, this Pokemon’s Psych Up attack does 40 more damage.
Weakness: Grass (x2)
Maybe we’ll get a Slowking BREAK since it doesn’t have a Mega Evolution?